Subject: Re: [PATCH 10/18] maccess: unify the probe kernel arch hooks

From: Christoph Hellwig <[email-masked]>
Date: Tue, 19 May 2020 07:46:06 +0200

On Thu, May 14, 2020 at 10:13:18AM +0900, Masami Hiramatsu wrote:
> > +		bool strict)
> >  {
> >  	long ret;
> >  	mm_segment_t old_fs = get_fs();
> >  
> > +	if (!probe_kernel_read_allowed(dst, src, size, strict))
> > +		return -EFAULT;
> 
> Could you make this return -ERANGE instead of -EFAULT so that
> the caller can notice that the address might be user space?

That is clearly a behavior change, so I don't want to mix it into
this patch.  But I can add it as another patch at the end.